I just did a little research and for the less experienced this is a good "Starting Primer" for learning about Pressures signs. This is truly a life long pursuit and you will eventually learn this, over time and this video is NOT a last word on the topic. So, be kind to yourself and "Start Low and Work Up" as the phrase goes..

I can't seem to find any 70K pressure loads for the 460 S&W. The Hodgdon website lists the maximum 4227 load with a 300 gr bullet as 40 gr compressed yielding 1988 fps and 57K PSI. 40 gr and a 300 gr Lee cast bullet would not even fit in the smaller 450 BM.

There has been no published evidence that a 460 S&W revolver is stronger than a 450 BM on a quality lower. The inconvenient fact that any revolver is wide open at both ends of the cylinder whereas as 450 BM is only open at the muzzle is comforting. I don't have an extra pile of 100s to do a blowup test on the two guns, although I do own both. Trust me, shooting a max 300 gr load in a 450 BM is like a 22 short compared to my 460XVR off its bipod.It's really a silly gun but the seller needed money.

If you can read and follow simple instructions you can reload any standard cartridge. Even a wild wildcat like my 22-06 is not dangerous to reload IF the chamber, throat, dies, powder, primer, cases and bullet all come together in harmony. Only WRA cases, only Redding BR dies, only magnum primers, only H869 and only a few strong .224 bullets that can take the twist and velocity. It's really just a 1930s version of the 22/244 IMP that finally has the components to realize its potential.

45-70 shooter wrote:I can't seem to find any 70K pressure loads for the 460 S&W. The Hodgdon website lists the maximum 4227 load with a 300 gr bullet as 40 gr compressed yielding 1988 fps and 57K PSI. 40 gr and a 300 gr Lee cast bullet would not even fit in the smaller 450 BM.

There has been no published evidence that a 460 S&W revolver is stronger than a 450 BM on a quality lower. The inconvenient fact that any revolver is wide open at both ends of the cylinder whereas as 450 BM is only open at the muzzle is comforting. I don't have an extra pile of 100s to do a blowup test on the two guns, although I do own both. Trust me, shooting a max 300 gr load in a 450 BM is like a 22 short compared to my 460XVR off its bipod.It's really a silly gun but the seller needed money.

If you can read and follow simple instructions you can reload any standard cartridge. Even a wild wildcat like my 22-06 is not dangerous to reload IF the chamber, throat, dies, powder, primer, cases and bullet all come together in harmony. Only WRA cases, only Redding BR dies, only magnum primers, only H869 and only a few strong .224 bullets that can take the twist and velocity. It's really just a 1930s version of the 22/244 IMP that finally has the components to realize its potential.

Hey Shooter, there ain't no-way I'd load the 460 SW to 70k PSI. When it came out those numbers were selling devices and since the introduction cooler heads have prevailed and down graded those numbers. That Hodgdon sight has more accurately expressed far safer loads for the 460SW and let's face it 57k ain't no slounch..

I'm glad to hear you would not do that. Of course first you have to own one ......

As for 70K psi 460 loads, I'd sure be interested to see a link to the source of your "70K psi" claim.

In all my loading books from both powder and bullet companies as well as 10 years back issues of Handloader, nobody ever mentions any load that approaches 70K psi. A damn fool could probably do it in a Ruger #1 and there are plenty of them holding forth on the internet.

Like the "experts" who said my Lil Gun 450 BM load was "dangerously underloaded". Same crowd who believes the 4831 "detonation" stuff but can never produce a dismembered gun.

I am very new to the idea of big-bore ARs, but already reload for other, more standard calibers. I am looking to purchase a 20" Bushmaster upper, and want to reload for it. I have read in places about the 450 Corvette conversion being done. My question is, if I stick to published data for the 450 Bushmaster is the conversion necessary? Or is the published data from Hornaday good to use without the conversion?

I am very new to the idea of big-bore ARs, but already reload for other, more standard calibers. I am looking to purchase a 20" Bushmaster upper, and want to reload for it. I have read in places about the 450 Corvette conversion being done. My question is, if I stick to published data for the 450 Bushmaster is the conversion necessary? Or is the published data from Hornady good to use without the conversion?

Welcome aboard and sorry I did not get time to do forums and emails until now. IMHO, unless you're experimenting near the upper limits of reloading for this caliber, the standard, carbine gas port will suffice. After you've been reloading for this caliber for a while and gain some insights into the impact of stout loads upon it, you will know whether the rifle length gas port is a good fit for what you use your rifle for.

Sorry if that sounds nebulous.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

I am very new to the idea of big-bore ARs, but already reload for other, more standard calibers. I am looking to purchase a 20" Bushmaster upper, and want to reload for it. I have read in places about the 450 Corvette conversion being done. My question is, if I stick to published data for the 450 Bushmaster is the conversion necessary? Or is the published data from Hornaday good to use without the conversion?

I agree with Hoot, naturally. Try some of the standard loads from the Hornaday reloading manual first before you step out. In addition to the taper crimp, which the Hornaday dies provide, you can also use the stab crimp. This is covered elsewhere in this forum. Most people reloading this round use the lil' gun powder. 38 or 41 grains seem to be the best loads.